Electric switch.



L. L. TATUM. ELECTRIC SWITCH. APPLICATION man Nome; 1911.

1 ,9558 Q72 1 Pmemed Mar. 12, 1918,

J- f y' earn an oration.

LEWIS I4. TATUM, OF MILWAUKEE, VZISCONSIN, ASSIGNOR, TO THE CUTLER-HAMMER MFG. 60., 0F MILWAUKEE; VTISCONSIN, A CORPORATION OF WISCONSIN.

ELECTRIC STVITCH,

Specification of Letters Patent.

Patented Mar. 112, 191%..

Application filed November 6, 1911. Serial No. 658,872.

To all whom it may concern Be it known that T, Lewis L. TA'rUM, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of 'VVisconsin, have invented new and useful Improvements in Electric Switches, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to improvements in electric switches.

It is one of the objects of my invention to provide a simple and e'flective snap switch movement.

It is a further object of my invention to provide a switch adapted to use in connection with a solenoid to intermittently energize and deenergize the same.

A further object of my invention is to provide a switch which when used in the relation mentioned will insure a full stroke of the solenoid plunger prior to energization and deenergization of the solenoid.

Various other objects and advantages of my invention will be hereinafter clearly and fully set forth.

For the purpose of more clearly disclosing the nature and characteristic features of my invention, I shall describe the embodiment thereof illustrated in the accom- Tapying drawing. It should bcunderstood however, that my invention is not limited to the specific embodiment thereof chosen for the purpose of illustration, but is susceptible of embodiment in various dilferent forms and of use in various diri'erent relations.

In the accompanying drawings Figure 1 is a front elevation of the device.

Fig. 2 is a plan view of the switch mechanism shown in Fig. 1, and

Figs. 3, 4, 5 and 6 are schematic views showing the switch parts in difl'e'rent. positions.

The device chosen for the purpose of illustration comprises a solenoid 1 and a switch S. The solenoid 1 is mounted in a suitable frame 2 secured to an insulating panel 3.

The solenoid is provided with a movable cessive reciprocations of its plunger.

able device, as for example, a step by step rheostat.

The. function of the switch S is to make and break the circuit of the solenoid 1 at the limits of movement of its plunger 4 thereby intermittently energizing and deenergizing said solenoid and causing suc- The switch mechanism includes two leaf spring contact members 6 and 7. These members are secured to'and supported by posts 8 and 9 respectively, suitably mounted upon the panel 3. Any suitable means such as bolts 10 may be employed to secure the contact members to the posts 8 and 9. The contact members 6 and 7 are provided with laterally extending overlapping contact tips 11 and 12 respectively. These contact tips may in practice be of any desired material but ll prefer to form the same of silver. The spring contact members 6 and 7 have an inherent tendency to cause their tips to mechanically contact. They may be used to control the circuit of the solenoid 1 in any preferred manner. As illustrated they are connected in series with the solenoid winding completing its circuit when their tips are in mechanical contact and interrupting its circuit when their tips are out of engagement.

The contact members 6 and 7 are adapted to be controlled to make and break circuit by an insulating cam member 14 operated by the solenoid plunger. As illustrated it comprises an insulating block rigidly secured to an arm 15 fulcrumed on a stud 16 projecting from the panel 3. The arm 15 is provided with an car 17 connected by a link 18 to the solenoid plunger 4, whereby the cam member is operated by the solenoid. Of course in practice the cam member might be connected to the solenoid plunger in various other ways than that illustrated.

Briefly described the function of the cam member is as follows :\Vhen moved upwardly it engages and places both contact members under tension and when moved to a certain angular position releases the contact member 6 the shorter of the two contact members allowing it to spring away from the member 7, but also allowing the member 7 to follow and remain in engagement with the member 6 for a limited period. It holds the member 7 under tension until I engages the contact member 6 and moves the served from Figs. 1 and same in an opposite direction to that previously described, at the same time holding it out of contact with the member 7 \Vhen the cam member reaches a certain angular position in this direction it again releases the contact member 6 which immediately iprii zigs back into contact with the mem- The foregoingis accomplished by providing the extremity of the cam member with .the beveled surfaces 20 and 21 forming a linear crest and by so proportioning the member 6 as to pass said crest in predetermined angular positions of the cam.

I shall now more specifically describe the operation of the switch mechanism in connection with the schematic views 3 to 6 inclusive. Assuming the parts to be in the positions illustrated in Fig. 1 energization of the solenoid will rock the cam member 14 upwardly causing it to strike the contact member 6, thereby forcing both contact members 6 and 7 upwardly as shown in Fig. 3. When the cam member has reached a certain' angular position, the contact member 6 will pass over the crest 23 as shown in Fig. 4:. When thus released from the cam member the contact member 6 immediately tends to snap back to its normal position illustrated in Fig. 1 and away from the contact member 7. The contact member 6 does not how'- ever immediately disengage its cotiperating contact member 7. As will readily be ob- 3 the member 7 during upward movement 0% the cam is held in a spaced relation therewith, due to its.

intermediate engagement with the member 6. Accordingly upon release of the member 6 the member 7 will follow and remain in engagement with the member 6 until the former engages the cam member. Thereupon the movement of the member 7 is checked and said member separated by the continued movement of the member 6 as illustrated'in Fig. 5. It will thus be seen .that contact between the members is not broken until after the lapse of a temporary period after the member 6 passes the crest of the cam member, the duration of which period is of course dependent upon the degree of tension of the contact members and leasing point.

the normal distance of separation of the member 7 and'the cam member. These two factors may of course be regulated 'at will to prolong or shorten the period during which contact between the members is maintained after the .cam member has reached the re- It will thus be readily observed that the movement of the cam may be made directly proportional to the movement of the solenold plunger and that the switch parts may be so adjusted as to permit the solenoid plunger to seal before contact is broken and its operating winding deenergized. This of course positively insures a full upward stroke of the solenoid plunger, in no wise dependent upon the inertia of the moving parts.

Due to the sudden check of the contact member 7 and the tension of the member 6, said members are separated with a snap action thereby quickly disrupting any are produced between the same. Further as the contacts separate the insulating cam member enters between the same thereby preventing the member 6 upon its rebound from contactingwith the member 7.

Assuming that the solenoid is deenergized, the cam would be rocked. downwardly. Upon such movement the cam engages and depresses the contact member 6 and at the same time holds contact member 7 out of engagement with the member 6. Continued downward movement of the cam further depresses the member 6 until said cam reaches such an angular position as to allow the member 6 to spring over the crest thereof. When this occurs the member 6 immediately springs back into contact with the member 7. Circuit is thereupon reestablished through the solenoid and the cycle of operation above described is then repeated. By properly proportioning the parts of thedevice the contact member 6 may be held against return movement until the solenoid plunger has reached its lower limit of movement. This insures a full down stroke of the solenoid plunger What I claim as new and desire to secure by Letters Patent is 1. In an electric switch, in combination, resilient cotiperating contacts tending to engage and means to move both of said contacts without disturbing the relation thereof and upon a predetermined degree of movement to release one and to restrain the other for effecting disengagement thereof. 0

.2. In an electric switch, in combination, resilient cotiperating contacts tending to engage, and means to move both of sald contacts without disturbing the relation thereof and after a predetermlned degree of such 116 movement to release one and restrain the other but permitting a limited return movementof the latter with the former.

3. In an electric switch, in combination, coiiperating contacts, one of the same being 120 resilient and tending to enga e the other and controlling means for sai contacts to hold the same out of engagement and to tension and release said resihent'contact for engagement with the other.

4. In an electric switch, the combination with resilient coiiperatin contacts tending to engage and means mova 1e in one direction to move said contacts together and after a predetermined degree of such movement 180 to release one and restrain the other for effecting disengagement of said contacts and in an opposite direction to tension and trip said released contact for reengagement with the other. l

5. In an electric switch, in combination, cooperating resilient contacts tending to en gage and controlling meansoperable to move said contacts together and in a critical posi tion thereof to release one contact while restraining the other, said means being also operable to place said released. contact under a reverse tension and upon reaching a critical position to release the same for reengagement of said contacts.

6. In an electric switch, in combination,

I two resilient contacts tending to engage and controlling means therefor including an operating and tripping member cooperating therewith to effect disengagement and reengagement thereof with a delayed action upon movement of said member to critical positions.

7. In an electric switch, in combination, cooperating movable contacts, and means including a cam member to effect engagement and disengagement thereof and to so position the same prior to their engaging and disengaging operations as to insure delayed cffect of such operations, I

8. In an electric switch, in combination, cooperating movable contacts and means including a cam member coacting'therewith to effect engagement and disengagement thereof and to so position the same prior to their engaging and disengaging operations as to insure an undisturbed relation thereof during an initial part of each' of such operations.

9. In an electric switch, in combination, normally engaged yielding contacts, and a cam member to move said contacts and in critical positions to effect disengagement and reengagement thereof, said member so positioning said contacts prior to their disengaging and reengaging operations as to delay completion thereof after, critical positioning of said member.

10. In combination, a solenoid having a movable plunger, a switch for making and breaking the circuit of said solenoid, and an operative connection including a cam member between said switch and the plunger of said solenoid to effect opening and closing of said switch with a delayed action upon critical movements of said plunger,

. In witness whereof I have hereunto subscribed my name in the presence of two witnesses.

Lnwrs n. TATUM. 

